Throwable robot with clamshell body

ABSTRACT

A two wheeled throwable robot comprises an elongate chassis with two ends, a motor at each end, drive wheels connected to the motors, and a tail extending from the elongate chassis. A rear portion having a deep recess securing the pair of motors with brackets, and batteries with brackets. The forward part having a shallow recess with a printed circuit board secured therein having control circuitry. The wheels are less than six inches in diameter and the robot weighs less than five pounds.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 16/103,851, filed Aug. 14, 2018, now U.S. Pat. No. 10,683,045,issued Jun. 16, 2020, which claims the benefit of U.S. Pat. No.10,046,819, issued Aug. 14, 2018, filed Jun. 23, 2015, which claimspriority to U.S. Provisional Application No. 62/015,889, filed Jun. 23,2014, the disclosures of which are incorporated by reference herein intheir entireties.

BACKGROUND OF THE INVENTION

Throwable robots for use in military and police operations need to behighly durable and robust to reliably perform under difficultconditions. Ideally such robots can absorb substantial falls, and othershock conditions, moisture, and other contaminants. Any incrementalimprovements in reliability and performance for robots used in highstakes military and police operations are desirable.

Known two wheeled throwable robots are disclosed, for example, in U.S.D637217, Publication U.S.20100152922, the contents of which areincorporated by reference herein. Conventionally tubular bodies areutilized for the chassis of the robots.

SUMMARY OF THE INVENTION

A two wheeled throwable robot comprises an elongate chassis with twoends, a motor at each end, drive wheels connected to the motors, and atail extending from the elongate chassis. The chassis split length wiseand comprised of a pair of elongate portions, a rear portion and aforward portion. The rear portion having recesses and brackets forcontaining and securing the pair of motors, recesses defined at each endincluding at the motors for receiving a pair of batteries. Adjoiningrespective surfaces join with a gasket or sealing material therebetween.

The chassis is generally cylindrical with modified surfaces and issplit, looking at an end, in a vertical chord forward of the axis of themodified cylinder. This provides a clamshell part with deeper recessesfor the motors and batteries, the high volume components, and a shallowclamshell part that retains the main printed circuit board. A featureand advantage of the layout is the vulnerable PCB is secured in ashallow component that has a high degree of structural strength with acentral region projecting forward and flattened forward facing endportions.

Moreover the rearward deeper clamshell part has two openings for thewheel shafts entirely contained within the ends of the deeper clamshell.Additionally, in embodiments, an annular bushing, unitary with thedeeper clamshell part, is entirely included and extends towards andcooperatively engages the forward shallow clamshell part in recess. Afeature and advantage of this structure is that it provides enhancedsheer resistance at the clamshell juncture whilst providing enhancedwheel shaft support.

A feature and advantage of embodiments is that even with the small size,modularity allowing, for example, different motors and different radios,has been built in.

A features and advantage of embodiments of the invention over known artthrowable robots is that the assembly has a reduced mechanical partcount resulting in reduced manufacturing costs.

A features and advantage of embodiments of the invention over known artthrowable robots is increased internal volume for battery and motorswith essentially the same size body as prior art robots.

A feature and advantage of embodiments of the invention over knownthrowable robots is greatly reduced number of interfaces to seal andsealing surfaces that are easier to seal. The design is believed to meetIP67 standard overall.

A feature and advantage of embodiments of the invention over knownthrowable robots is integration of the blister elements reduces theeffective diameter which can decrease the likelihood of direct impactwith the outer surface.

A feature and advantage of embodiments of the invention over knownthrowable robots is a novel motor mounting system which can accommodatemore motors, and is more reliable.

A features and advantage of embodiments of the invention over known artthrowable robots is a novel antenna mounting system which is waterproofand easily reconfigurable. Moreover, an embodiment formed of Nitinol ishighly robust and returns to its original orientation.

A feature and advantage of embodiments of the invention over knownthrowable robots is support for conformal antennas is also in place.

A feature and advantage of embodiments of the invention over knownthrowable robots is that the chassis provides for modular radiosupport—the chassis readily receives and supports industry standardradios, enabling the robot to have digital, spread-spectrum, frequencyhopping, encrypted and mesh radio communication. Also enables multipledata streams that can be turned on and off remotely. Further enablesactivation and deactivation of functionality (e.g. IR LEDs)

A feature and advantage of embodiments of the invention over knownthrowable robots is an Integrated digital video—can be processedonboard, video overlays can be added

A feature and advantage of embodiments of the invention over knownthrowable robots is an elimination of vignetting—Previous robots couldhave vignetting in the image caused by alignment of the image sensorwithin the camera and the hole in the protective shell. By integratingthe lens into the clamshell, this problem has been eliminated.

A feature and advantage of embodiments of the invention over knownthrowable robots is a significantly increased processing power (can nowprocess video onboard, potential for increased autonomy).

A feature and advantage of embodiments of the invention over knownthrowable robots that contributes to the modularity, is that all majorcomponents connect through board to board connectors. With the exceptionof coaxial cables to the antennas and the wires on the leads of themotors and the charge plug, all wire harnesses have been eliminated.There is no longer any soldering required in final assembly (only on PCBpopulation).

DESCRIPTION OF THE FIGURES

FIG. 1 is a front perspective view of a throwable robot according to theinventions herein.

FIG. 2 is an exploded view of the rearward clamshell part illustratingmotors and brackets.

FIG. 3 is an exploded view of the rearward clamshell part illustratingthe batteries and brackets.

FIG. 4 is an exploded view of the forward clamshell part.

FIG. 5 is an elevational view of the forward clamshell part with aprinted circuit board therein.

FIG. 6 is a partial plan view of the robot of FIG. 1 with the chassisremoved illustrating the arrangement of the components.

FIG. 7 is an end view of the chassis clamshell parts.

FIG. 8 is a perspective view of the deeper recess clamshell part withoutcomponents.

FIG. 9 is a perspective view of the shallow recess clamshell partwithout components.

DETAILED DESCRIPTION

A two wheeled throwable robot comprises an elongate chassis 40 with twoends 42, 44 and with exteriorly exposed surface 41, a motor 49 at eachend, drive wheels 52 connected to the motors, and a tail extending fromthe elongate chassis. The chassis split length wise and comprised of apair of elongate portions, a rearward portion 56 and a forward portion57. The rearward portion having a C-shape cross section with exteriorlyexposed flattened portions 60, 61. The rearward portion having recesses64 and brackets 66, 67 for containing and securing the pair of motors49, recesses defined at each end including at the motors for receiving apair of batteries 74. Adjoining respective surfaces 75, 76 join with agasket or sealing material therebetween.

The chassis is generally cylindrical with modified surfaces and issplit, looking at an end, in a vertical chord forward of the axis of themodified cylinder. This provides a clamshell part 80 with deeperrecesses 81 for the motors and batteries, the high volume components,and a shallow clamshell part 82 with a shallow recess 83 that retainsthe main printed circuit board 28. A feature and advantage of the layoutis the vulnerable PCB 28 is secured in the forward portion 57, a shallowcomponent that has a high degree of structural strength with a centralregion 88 projecting forward and flattened forward facing end portions90, 91.

Moreover the rearward deeper clamshell part has two openings 92, 93 forthe wheel shafts entirely contained within the ends of the deeperclamshell. Additionally, in embodiments, an annular bushing 95, unitarywith the deeper clamshell part, is entirely included and extends towardsand cooperatively engages the forward shallow clamshell part in a recess97. A feature and advantage of this structure is that it providesenhanced sheer resistance at the clamshell juncture whilst providingenhanced wheel shaft support.

The robot described here is one incorporating video, audio, and lightsensing with improved environmental sealing. The two-piece unitarychassis with a protective shell and blister have been replaced with aclamshell design. This reduces the number of interfaces to seal from 38down to 12. The microphone, light sensor, LED illuminators 19, and blindhole 102 for the activation pin 105 from the prior art robot blisterhave been moved to the front half of the clamshell design while thecharge port has been located in the rear half of the clamshell. Themicrophone port is sealed with an acoustic waterproof vent, rated toIP67, provided by W. L. Gore. The charging jack is IP67 rated unmatedand has additional circuitry which will prevent the battery fromshort-circuiting across the charge jack terminals, which may happen, forexample, if it is exposed to saltwater. This circuitry is deactivatedwhen the robot is off because the battery's circuitry itself will ensurethe battery is protected. The illumination LEDs, 19 light sensor, ande-ink display are covered with windows with clear VHB double-sided tape.The clamshell halves are held together by screws with an elastomericgasket 16 in between the two halves for sealing.

By switching to the clamshell design, increased volume has been madeavailable without a significant increase in size. Accommodations havebeen made to support two battery packs to support increase power draw ofnew electronics and increase runtimes. In addition, the motors now mountdirectly to the rear of the clamshell. This provides heatsinking andadditional volume has been left to accommodate other models of motors(brushed with increased torque, brushless motors, etc). The motorclamping has been revamped with a two piece hold down which is animprovement over the prior art throwable robots, which was cantilevered,resulting in high bending stress on the screws and a relativelyunreliable clamp.

There is a micro-clutch assembly 12 built onto the axle. End caps havebeen eliminated and integrated into the main clamshell housing. Likebefore, spring-energized seals from Bal-Seal are employed for theshafts. Combined, this reduces part count and potential water and dustingress. The shape of the shafts have been modified now to ensure theshaft seal only contacts smooth edges during the installation of theclutch assembly.

The electronics have been reconfigured to fit on a single primary boardassembly (PCB). This primary board has an integrated camera 110,microcontrollers, microphones, photovoltaic light sensor 17 (used todetermine when to activate LEDs), LEDs, hall-effect sensor (foractivation via magnet embedded into the actuation pin 105), an industrystandard modular radio interface connector, battery management,processing interface (presently an interface to a system on a module(SOM) that mounts as a daughter board), a breakout the “interfaceboard”—a 2nd daughter board (which provides interfaces for the chargereceptacle, brushed and brushless motors, and the dual batteryconfiguration), gyroscopes, accelerometers, magnetometers, an e-inkdisplay, and battery management system. This board also provides filtercircuitry to selectively reduce motor noise which can be selectivelyenabled or disabled based on the robots motion.

Due to the camera sensor being directly integrated into the main PCB,the lens for the camera has been integrated into the front half of theclamshell. This lens is sealed in to prevent ingress of water or dust. Aprotective sticker can be used to protect against scratching. Previouslythe antennas were whip antennas made from braided steel cables coated inplastic. The whip design is critical to get the signal away from groundeffects, but still possible to deform upon impact. Two antennas mountingpoints have been developed. The first is front-mounted and providesincreased ease of assembly. The second is top mounted and provides forincreased height and eliminates a portion of the robot from blocking theantenna signal and introducing directionality. In both cases, there issupport for diversity or MIMO communication through the use of multipleantennas. Two antenna designs were considered. The first is a conformalantenna that wraps around the front portion of the body. The second is awhip made of a special blend of Nitinol, a shape memory alloy. Superiorrange has been achieved with the Nitinol whips. The properties ofNitinol are appealing as they can deform on impact and then returnupright when the robot self-rights where previous whip antennas woulddrag on the ground and cause variability in range. Previous antennaswere crimped onto a threaded fastener which were then screwed intoplace. Adhesives were then applied to prevent moisture ingress. The newantennas utilize a cartridge approach which has a small PCB th matchingcircuitry and a pin receptacle mounted on a cartridge that is insertedfrom the top of the robot and held in place with an e-ring. A pin iscrimped onto the Nitinol braid and a cap is fit around an insulator thatis fit around the antenna. Silicone is used to seal the top of the cap.These antennas can be replaced in the field by removing two externalscrews and sliding an antenna out. A feature and advantage ofembodiments of the invention over known throwable robots thatcontributes to the modularity, is that all major components connectthrough board to board connectors. A feature and advantage ofembodiments of the invention over known throwable robots thatcontributes to the modularity, is that all major components connectthrough board to board connectors.

In embodiments the robot wheels are less than 6 inches in diameter. Inembodiments, less than 5 inches. In embodiments, less than 4 inches. Inembodiments, the robot weighs less than 5 pounds. The features of therobot of Publication U.S.20100152922 may be incorporated in the robotclaimed and described herein. Said reference is incorporated byreference herein.

1. A throwable robot comprising: an elongate chassis having an outwardlyexposed surface extending around the chassis, the chassis splitlengthwise and having an interior, a pair of drive motors positioned andsecured in place in the interior, one on each of two opposing ends, abattery secured in the interior; a pair of motor driven drive wheelsattached to each end of the chassis, each of the pair of motor drivenwheels having a diameter of less than 6 inches; and a tail extendingfrom a rearward face of the elongate chassis, the throwable robotweighing less than 5 lbs.
 2. The throwable robot of claim 1, wherein thechassis has a deep recess portion that is rearwardly positioned and towhich the tail is connected.
 3. The throwable robot of claim 1, furthercomprising a circuit board positioned internally forward of the pair ofmotors, the circuit board having a camera secured thereto, the cameradirected forwardly though an opening in the chassis.
 4. The throwablerobot of claim 3 wherein the chassis has a camera lens secured to thechassis at the opening.
 5. The throwable robot of claim 1, furthercomprising a printed circuit board having a microphone, a camera, andillumination LED's attached thereto at a forward face of the chassis andexposed outwardly of the chassis.
 6. The throwable robot of claim 1wherein each of the wheels is less than 5 inches in diameter.
 7. Thethrowable robot of claim 6 wherein each wheel has a shaft extendingthrough an aperture in the deep recess portion, each shaft sealed with ashaft seal.
 8. The throwable robot of claim 3, wherein the circuit boardwith camera spans a recess portion of the chassis in the interior. 9.The throwable robot of claim 8 wherein a light sensor, and a pluralityof illumination LED's are attached to the printed circuit board.
 10. Athrowable robot comprising: an elongate body supporting a pair of drivewheels, one drive wheel on each of two ends of the body, a tailcentrally positioned on the elongate body intermediate the pair of drivewheels and extending rearwardly from the body; the elongate bodycomprising an elongate chassis with an elongate deep recess, a pair ordrive motors secured to the chassis in the deep recess, and a batterypositioned in the deep recess, a printed circuit board with controlcircuitry secured within the chassis, and a camera in the chassis anddirected forwardly; the pair of drive wheels attached at each end of thechassis, each of the pair of wheels being gear driven by a respectivemotor.
 11. The throwable robot of claim 10 wherein the printed circuitboard has the camera attached thereto and positioned at an opening in aforward portion of the chassis, the opening having a lens securedthereto.
 12. (canceled)
 13. The throwable robot of claim 11, wherein theprinted circuit board has a microphone and a photovoltaic sensorattached thereto end and each positioned at openings in a forwardportion of the chassis.
 14. The throwable robot of claim 11, whereineach of the pair of wheels is less than 6 inches in diameter.
 15. Thethrowable robot of claim 14, wherein the robot weighs less than 5pounds.
 16. (canceled)
 17. The throwable robot of claim 10 wherein thechassis has flattened portions on a forward side, a top side and abottom side of the chassis.
 18. The throwable robot of claim 10 whereina shallow component of the chassis is forwardly positioned and has acentral region projecting forwardly and further having flattened forwardfacing end portions on each lateral side of the central region.
 19. Thethrowable robot of claim 10 wherein an actuation member for actuatingthe robot is positioned at a forward face of the chassis.
 20. (canceled)21. A throwable robot weight less than five pounds comprising: anelongate body supporting a pair of drive wheels, one drive wheel on eachof two ends of the body, a tail centrally positioned on the elongatebody intermediate the pair of drive wheels and extending rearwardly fromthe body; the elongate body comprising an elongate chassis with anelongate deep recess, the chassis having a flattened portion on a topside, a flattened portion on a bottom side, and a flattened portion on aforward side, the robot further comprising a pair or drive motorssecured to the chassis in the deep recess, a battery in the deep recess,a printed circuit board with control circuitry secured within thechassis, and a camera in the chassis and directed forwardly the pair ofdrive wheels attached at each end of the chassis, each of the pair ofwheels being gear driven by a respective motor.